Industrial bulk material transportation

ABSTRACT

An industrial railway is provided wherein a train of cars is propelled along a track by motor-driven friction wheels at intervals along the track which contact friction strips along the sides of the cars. The cars are dumped while the train is moving by successively tilting them sideways, but cooperating means on the track and cars keep the cars on the track. Unloading stations include adjustable and mobile arrangements so that dumping of the load may take place at different locations without moving the track.

United States Patent 191 Robinson, Jr. et al.

[45] Aug. 14, 1973 INDUSTRIAL BULK MATERIAL TRANSPORTATION [75]Inventors: Melville W. Robinson, Jr., Beaver;

Charles M. Jaco, Jr., Upper St. Clair Twp., Allegheny County, both ofPa.

[731 Assignees Dravo Corporation, Pittsburgh, Pa.

[22] Filed: Nov. 18, 1971 [21] Appl. No.2 199,865

[52] US. Cl. 214/41, 104/168, 214/1 MS, 214/62 A, 238/11, 238/284 [51]Int. Cl. 865g 67/04, 865g 67/44 [58] Field of Search 214/62 R, 62 A, 41;104/168; 238/11, 284

[56] References Cited UNITED STATES PATENTS 282,125 7/1883 Simar et214/62 A 2,954,744 10/1960 Bonner 104/168 2,055,571

9/1936 Bruneti 238/284 3,039,402 6/1962 Richardson 104/168 2,979,1844/1961 Becker et a1 214/62 R FOREIGN PATENTS OR APPLICATIONS 1,235,3815/1960 France 104/168 Primary ExaminerRobert G. SheridanAtt0rney--William H. Parmelee [57] ABSTRACT An industrial railway isprovided wherein a train of cars is propelled along a track bymotor-driven friction wheels at intervals along the track which contactfriction strips along the sides of the cars, The cars are dumpedwhilethe train is moving by successively tilting them sideways, butcooperating means on the track and cars keep the cars on the track.Unloading stations include adjustable and mobile arrangements so thatdumping of the load may take place at different locations without movingthe track.

20 Claims, 27 Drawing Figures Patented Aug. 14, 1973 3,752,334

8 SheetsSheet 1 Patented Aug. 14, 1973 8 Sheets-Sheet 2 INVENTOHSMELV/LLE Hf ROBINSON, Jr. CHARLES H. JACO, Jr.

h mhml By)?" i f be Attorneys Patented Aug. 14, 1973 3,752,334

8 Sheets-Sheet 3 INVENTORS MEL V/LLE W. ROBINSON, Jr.

ems/ass 41. M00, .0.

W fire/r Aflomeys Patented Aug. 14, 1973 8 Sheets- Sheet 4 N /l AINVENTORS MELV/LLE W ROBINSON, Jr

CHARLES H. 'JACO, Jr.

Wv 7 M Meir Aflameys Patented Aug. 14, 1973 8 Sheets-Sheet 5 INVENTORSMEL V/L LE W. ROBINSON, Jr

CHAR .512 M. MCO, Jr. 5 fluwuk Zflr/ W y their Attorneys Patented Aug.14, 1973 8 Sheets-Sheet (3 .3 1 mm g Wt Wm k2 INVE'A/Tk MELV/LLE W.ROBINSON, Jr. CHARLES M. JACO, Jr.

Em IMP M, W 1 WM their Attorneys Patented Aug. 14, 1973 8 Sheets-Sheet 7M 49/! Atfarneys Patented Aug. 14, 1973 3,752,334

8 Sheets-Sheet 8 zvvnvrops MELV/LLE w. ROBINSON, Jr. CHARLES H. .1400,Jr.

their Attorneys INDUSTRIAL BULK MATERIAL TRANSPORTATION This inventionrelates to the transporation of material, especially bulk material byrailways, and more especially railways in which a train of cars ispropelled by trackside driving means located at intervals along thetrack rather than by a locomotive or other selfcontained motive power.

In numerous environments, as for example in open pit mining operations,strip mining, quarrying, mineral processing plants, leaching andland-fill operations, large quantities of bulk material must be hauledfrom one location to another. It is commonly necessary in such cases tochange the place of loading or unloading the material into transportvehicles as earth or mineral deposits are removed, or as land-fillprogresses, or as other change takes place. At the present time suchoperations are usually effected with a fleet of automotive dump trucksthat travel at least in part over temporary roadways between the loadingand unloading stations or terminals. This is expensive, especially fromthe standpoint of truck maintenance including rapid deterioration, andthe replacement of tires due to rapid wear. Another important item ofexpense is the fact that each truck must have at least one operator atall times that the truck is in use, both in actual transport of materialand during loading and unloading of the truck. Another cost factor isthe grading and upkeep of the temporary roads for all-weather use.

Narrow gauge railways are sometimes used with internal combustionpowered locomotives, but in such case the track must be well laid andbedded to accept the weight of the locomotive and the thrust of itswheels against the rails in pulling the train or in braking, so that theinitial cost of the track is high and its relocation to keep up with theexcavation or place of disposal is costly. The road bed must be limitedto quite low grades, and the establishment of maximum grades is afurther factor to the usefulness or economy of such equipment. If morethan one train is used, this expense is increased, double trackage orswitches then being necessary. Often with locomotive haulage, severaltrains may be required for efficient handling of bulk materialespecially for hauling material over a distance of a mile or more. Thisentails the use of an engineer for each train, and as with automotivetrucks, the engineers empty return time and standby for loading andunloading is unproductive.

Railways have heretofore been proposed where trains are propelled byfriction wheels or belts arranged at intervals along a track sopositioned as to engage drive strips along the sides of the cars topropel the train from one drive unit to the next. This enables veryinexpensive tracks to be used, since the track does not need to resistthe thrust or weight of a locomotive, and in such case the tracks may bemoved with relatively little expense. Also there can be much steepergrades because of the drive means being stationary with much moreeffective driving friction than can be secured between the drive wheelsof a locomotive and the rails.

As heretofore constructed, however, transportation systems of this kindhave not been extensively used because of loading'and unloadingproblems, particularly in respect to the difficulty in changing thelocation of the loading and unloading stations, and the cars themselveshave posed further difficulties. Perhaps the most successful of priorapparatus of this type of which we are aware is disclosed in Hubert US.Pat. No. 3,332,535, dated July 25, 1967.

SUMMARY OF THE INVENTION According to the present invention, the carsare each formed with a chassis made of structural sections with areadily replaceable strip extending lengthwise of each car. These stripsare covered with a slightly resilient friction material, such assynthetic or natural rubberousmaterial, elastomer polyurethane of 95durometer being a particularly tough, high-friction material suitablefor the purpose. The cars are closely coupled through universalcouplings, and except for the lead, and perhaps the rear end car, eachpreferably has a single axle at one end and the other is supported onthe axle end of an adjacent car. Each car has a hopper-like ortrough-like body with substantially open ends supported thereon and atrough-like apron extends from one end of each car into the end of thefollowing car.

In a preferred embodiment the cars have no springs, and they arepreferably loaded on a resilientlysupported track section whereby theshock of dumping the bulk material into each truck in succession iscushioned by the track instead of the usual arrangement of springs onthe cars operatively interposed between the vehicle wheels and bed.Unloading is effected by progressively tipping the cars in succession toone side through an are sufficient to discharge the contents, perhaps asmuch as about while the cars remain connected to each other with aunique holding arrangement for keeping the cars on the track. Afterdumping, the cars are restored to their normal upright position.

The unloading terminal may be variously constructed, depending on thenature of the operation. It may be simply an elevated track thatprogressively tilts the cars sideways as the train moves therealong, orit may be a structure which is itself movable along the track with aramp at each end having rails so arranged that the train will ride fromthe true trackage, up a ramp, be dumped, and then down another ramp backon the true trackage, or it may be a mobile structure mounted on atractor unit or other movable supporting unit.

The railway of the present invention is adapted especially to extensiveopen pit mining operations, such as copper mining, and will hereafter bedescribed particularly in connection with such an operation, for thepurpose however of illustration and without excluding a wide variety ofother operations to which it is adapted. In open pit mining of copper,high-grade ore which is produced is sent directly to a smelter or othermetalextracting or beneficiating plant. There is also produced low-gradeore too poor for smelting and which is deposited in beds on the earththrough which acid is percolated to leach out the metal values and theseepage into the earth from this bed is collected and processed for therecovery of metal. There is also produced on abundant quantity ofoverburden and rock that is of no value for processing for the recoveryof metal ane which must be transported to a land-fill or dump. Thepresent invention lends itself to this type of mining in that: (l) theloading terminal can be moved as the pit develops; (2) mobile unloadingstations can deposit the unwanted material in a land-fill in aneffective manner; (3) the mobile unloading terminal enable the leachingbeds for low-grade ore to be developed in layers with provision for therecovery of the spent acid 3 from which the metal values are recoveredand trains loaded with high-grade ore can be sent directly to thesmelter or other metal extraction or ore-beneficiating operation.

BRIEF DESCRIPTION OF THE FIGURES Our invention may be more fullyunderstood by reference to the accompanying drawings showing a preferredconstruction and method, and in which:

FIG. 1 is a plan view of a train of cars;

FIG. 2 is a side elevation of FIG. 1;

FIG. 3 is a side elevation on a larger scale of a single car;

FIG. 4 is a broken top plan view of FIG. 3;

FIG. 5 is a transverse section in the plane of line VV of FIG. 3;

FIG. 6 is a side elevation of a loading station;

FIG. 7 is a transverse section in the plane of line VI-VI of FIG. 6;

FIG. 8 is a fragmentary detail on a larger scale of one of the shockabsorbers;

FIG. 9 is a more or less schematic elevation looking into a typicaldrive station for the train;

FIG. 10 is a top plan view of FIG. 9 with part of the structuralframework broken away;

FIG. 1 l is a side elevation of the driving unit of FIG. 9;

FIG. 12 is a schematic view of one form of dumping terminal for therailroad;

FIG. 13 is a transverse section through the track at a dumping station;

FIG. 14 is a schematic view elevation of another form of dumpingarrangement which itself is movable along the track and with a train ofcars, the cars being tilted to different angles;

FIG. 15 shows schematically in perspective the dumping arrangement ofFIG. 14 but without the cars;

FIG. 16 is a transverse section in the plane of line XVI-XVI of FIG. 15;

FIG. 17 is a transverse section in the plane of line XVII-XVII of FIG.15;

FIG. 18 illustrates in side elevation a loading station such as might beprovided on the entrance of an openpit mine;

FIG. 19 is a more or less schematic side elevation of a mobile unloadingterminal for stacking the unloaded material in a particular form of bed;

FIG. 20 is a schematic top plan view of the apparatus shown in FIG. 19;

FIG. 21 is a fragmentary schematic plan view of a desirable trackarrangement for use with any unloading station, but particularly theunloader of FIGS. 19 and 20;

FIG. 22 is a fragmentary side elevation showing one arrangement forkeeping the rail of the mobile unloading unit in register with thenon-movable track;

FIG. 23 is a transverse section in'- the plane of line XXIIIXXIII ofFIG. 22;

FIG. 24 is a schematic diagram indicated how an installation of thetransportation apparatus herein disclosed is adapted to an open-pitmining operation;

FIG. 25 is a view similar to FIG. 9 of a modified form of drivingstation where there are parallel track for trains moving in oppositedirections;

FIG. 26 is a view similar to FIG. 9 showing a modified form of drivingstation; and

FIG. 27 is also a view similar to FIG. 9 of another form of drivingstation.

The invention contemplates the organization of several components, someof which will be differently constructed for different specificrequirements, such as train loading and unloading stations, anddifferent forms of unloading stations may be used in one system. as, forexample, in the herein-described method of mining. The apparatus andarrangements herein illustrated and described indicated the adaptabilityof the invention to various situations or operations.

The Track The track, designated generally as T, is preferably anarrow-gauge two-rail track carried on cross ties. The rails aredesignated 2 and the ties 3. For the most part the track does notrequire very much grading, ties can be light-weight and may be widelyspaced, and light ballast is all that is needed. The loading andunloading track sections will be hereinafter described. Conventionaltrack switches and cross-overs may be used, as hereinafter more fullydescribed.

The Train and Cars The train is comprised of a succession of cars,desig-' nated generally as C, C and C, and C being at opposite ends ofthe train. The cars are all generally similar and of simpleconstruction, as best seen in FIGS. 3, 4 and 5. Each has a frameconprising a central longitudinally-extending I-beam 5 with sidechannels 6 extending parallel therewith, one at each side thereof butspaced from it, these channel sections having their flanges turnedtoward the center beam. At each end of the frame there are channelsections 7 and there are cross members 8 at the middle of the frame.

Bolted to the under surface of each channel member 6 of the cars C nearone end thereof is a journal box 9. The ends of an axle 10 are receivedin the opposed journal boxes on each car, the axle having flanged wheels11 spaced to ride on the rails 2. It will be noted that there are nosprings in the structure between the wheels and the frame.

On each car frame there is an open-ended open-top body designatedgenerally as 12. It comprises three spaced cradle-like cross frame 12asecured to the frame, one at each end, and one at the middle into whichis secured the material receiving body 13 of metal plate, the body thusbeing generally in the form of a trough with a flat bottom andupwardly-flaring sides.

At one end of each car there is a recessed coupling element of somekind, and at the other end there is a second coupling adapted to bereceived in the recessed coupling of an adjacent car, the twocomplementary couplings of adjacent cars allowing substantial universalmovement of one car relative to the next. The recessed element at oneend is designated 14 and the coupling at the othe end is designated 15.A transverse pin is designated 16. Ordinarily the train will operate asa unit and there will be no need for frequent coupling or uncoupling ofthe cars. The coupling is designed so that while the end of one car issupported on one end of another, each may rotate relative to the otherabout its longitudinal axis through a substantial are which may even beas much as The connection also permits some vertical movement of one carrelative to the adjacent ones.

The cars C and C are of the same construction as the cars C but thesecars have front and rear wheels and axles instead of only a single axle.With these two end cars having two axles and four wheels, the train mayrun in either direction, but obviously it is only necessary that one ofthe end cars have four wheels. Often times it may be desirable on allcars to have one or both wheels loose on the axle, especially if thetrack involves frequent sharp turns.

Removably attached to the outer face of the side channels 6 of each carare elongated metal plates coextensive with the length of the car andwhich have a rubber or rubber-like tread strip 21 on the outer facethereof. These strips are parallel to channels 6, except that as seen inFIG. 1 the corresponding strips on the two end cars and designated 22desirably converge in the direction of that end of the train on whichthey are located. It will also be noted that the top flange 6' of eachchannel 6 is unobstructed and clear of or spaced away from any part ofthe body. The purpose of the strips 20-21 and of the exposed top flangeof the side channels 6 will be hereinafter described.

As previously indicated, the body of the car in which the load iscarried comprises a trough-like structure 13 having a flat bottom 25 ofless width than the frame or chassis with upwardly and outwardly-flaringsides 26 received within transversely-extending cradles 13 secured tothe car frame. Each end of the body is open, but at one end of the bodyof each car there is secured an apron 28 which is preferably made ofheavy rubber or rubber-like material. This apron, shaped to conform tothe trough shape of the body, extends beyond the end of the car in whichit is secured into the open end of a succeeding car. Each car C has theapron 28 secured therein at one end, and at the other end receives thesimilar apron of the next-adjacent car. The terminal ends of end cars Cand C have end walls 29, but their opposite ends may either have such anapron 28 secured thereto or received therein, as the case may be.

The train therefore comprises an articulated continuous trough mountedon a succession of wheeled frames or carriages more or less flexiblycoupled so that each car may have limited vertical movement relative tothe ones to which it is connected, and also have limited rotationalmovement about its long axis relative to the ones at each end andtransversely thereto. The significance of this will be apparent from theside dumping to be hereinafter described.

The Driving Stations For propelling the train there are similar drivingstations at intervals along the trackway, these being generallydesignated as D. The spacing of these stations will depend on thetopography and the length of the trains. Upgrade they will almost alwaysbe sufficiently close that some portion of the train will engage onedriving station before leaving a previous one, and on steep grades, theymay be even closer. In a double-track system where cars move upgrade onone track and downgrade on the other, the drive stations may be arrangedto drive trains moving upgrade and as braking stations on trains movingdown. They may be further apart on substantially level tangents; thedrive stations may be further apart if they are located at a place wherethe train will be moving with sufficient momentum to travel betweenstations without applying power thereto. Also these stations may attimes function exclusively as braking stations.

Referring to FIGS. 9, l0 and 11 showing one form of driving station,there is a base structure 30 over which the rails 2 pass, and to whichthey are secured by bolts or other fasteners to restrain the railsagainst vertical or lateral movement. At each side of the track andspaced about equal distances from the rails are upright supportingstructures 31 and 32, each comprising at least two spaced verticalcolumns 33 welded or otherwise secured to the base 30 and connected atthe top by a structural section 34. A weather canopy or roof 35 isdesirably provided over the entire station. I I

On each of the columns 33 of upright structure 31 there are securedbearing blocks 36 for a cross shaft 37. There is a generally horizontalframe 38 that extends sideways away from the track and which ispivotally hung from the shaft 37. There is a cradle-like suspensionstructure 39 hung from this frame in which is an electric motor andspeed reducing gear and brake unit 40 with a depending driven shaft 41on which is a drive wheel 42 with a friction tread on its periphery. Thedrive wheels 42 are at the level of the friction strip 20-21 on thesides of the cars C.

There are compression springs 43 on the top of the pivoted frame 38 atthe end most remote from the cross-shaft 37. The upper ends of thesesprings are confined against fixed abutment members or brackets 44rigidly fixed on each of the uprights 33. Adjusting screws areschematically indicated at 45 to adjust these springs which have thedouble function of biasing the motor and drive wheel assembly that ispivotally hung from shaft 37 toward the cars of the train, and absorbingimpact when the front end of the train engages the driving wheel and thetapered friction strip 22 moves the wheel 42 against gravity and thepressure of the springs outwardly. With this arrangement the frictionwheel is resiliently urged against the strips 21-22 on the sides of thecars with the required traction to drive the train when the wheel 42 isbeing driven.

For opposing the lateral thrust of the drive wheel against the cars bythis arrangement, the upright col-- umns 33 of the opposite frame 32-hasbearing brackets 36' for a rock shaft 37. There is a laterally-extendingframe 38' extending outwardly away from the track on this shaft.Depending structural elements 39 support a bearing for shaft 41' onwhich is an idler wheel 42' at a level to engage the friction strips onthe other side of the train. Springs 43' are arranged similarly tosprings 43 between frame 38' and brackets 44', these springs urging thewheel 42' against the side of the car opposite the driving wheel 42 withsufficient pressure to keep the car centered and relieve substantially,if not entirely, the side thrust of the wheels on the rails.

Often two tracks may be side-by-side for trains moving in oppositedirections. In this case there may be a driving station such as shown inFIG. 25 where there are two motor-driven wheels, one at the outside ofeach track and normally driven in opposite directions and the thrustwhich corresponding to 42' is positioned to engage the friction strips21 of the cars going on either track. The arrangement may simply requirethe addition of another -motor-driven wheel 42 on the outside of theopposite track, or driving units may be similar to the units shown inFIG. 26, now about to be described.

Another form of drive is shown more or less schematically in FIG. 26where the friction wheels, instead of being resiliently supported, haveresilient pneumatic tires that press against the side strips of thesuccessive cars, somewhat similar to US. Pat. No. 3,039,402, Richardson,granted June I9, 1962.

There is a base structure 30a with spaced upright supports 31a and 32athereon and the track rails 2 are located between them. On each uprightsupport there is a vertical shaft 410 on which is a drive wheel 42a.Each drive wheel has a resilient tire, preferably an inflated pneumatictire 42b on its periphery. The two wheels and tires are so spaced thatas the front of the train with its rearwardly-diverging side strips20-21 will enter between the opposed tires and there will be a graduallyincreasing pressure between the tires and the cars to provide goodtraction between the wheels and the cars. As here shown only the rightwheel 42a is driven at the same speed if this is found to be desirableby a motor 400, but both may be driven.

As indicated above, FIG. 25 shows in slightly less detail essentiallythe arrangement shown in FIG. 26 but with the second driving assembly atthe outside of the second track. In this view, the same referencenumerals have been used to disignate parts which correspond to FIG. 26,and in additiion the middle wheel which replaces the left wheel 42a 42bof FIG. 26 has a driving motor 40C. This motor, like the others, mayalso be of a type used for regenerative braking. As explained above, themiddle wheel in FIG. 25 engages the drive strips of a train on eithertrack.

In the arrangement shown in FIG. 27 the car, disignated generally as Chas a laterally-projecting horizontal strip 20* thereon at each sidethereof. As here shown it extends from the sides of the body, and itpreferably has rubber strips 21- removably secured to the top and bottomflat horizontal surfaces thereof.

At the proper elevation the driving station has two pairs ofoppositely-driven resiliently-tired driving wheels 46 on horizontaldrive shafts 47, one pair being at each side of the track and so locatedthat the flangelike strips on the cars will enter the bight between thetires of the wheels 46 and be frictionally engaged thereby. The wheels46 and their shafts 47 are driven from a motor 48 through a commongearbox 49. Since the power from the motor is applied equally to thetrain between two driving wheels instead of one, slippage moving a heavyload is reduced, and by using pneumatic tires on the drive wheels, thepressure may be adjusted to effect the most efficient drive.

While there are a pair of wheels at each side of the train, there may beonly one pair, and since there is no side thrust by the friction wheelsagainst the cars, no idler wheel to oppose side thrust is required.

As above suggested, driving stations may also be braking stations, inwhich case the motors are regenerative or the friction wheels may beotherwise restrained from free rotation by friction brakes of anyappropriate type.

The Loading Station Since the cars preferably have no springs, and heavyloads of rock, ore or other cargo may be dumped from a chute, hopper,clamshell bucket or the like into the cars, some provision is made torelieve the shock. FIGS. 6 to 8 show one such arrangement. It may becompared somewhat to a bridgebetween two fixed ends of the track, thespan of the bridge being supported on shock absorbers that cushion thespan when a heavy load is dropped into a car positioned on or movingover the span.

More particularly, there are two fixed supports spaced from each other adistance greater than the length of one car and between these two areother supports 51 of lesser height. The main track rails 2 terminate onthe supports 50. There is a beam structure 52 spanning the distancebetween the supports 51. Above this there is a span 53 that isresiliently supported on the beam structure 52. The beam structurecomprises parallel I-beam sections 54, the spacing of which -is aboutthe same as the spacing of the track rails, and

they are connected by structural sections 55.

The span 53 is likewise comprised of parallel I-beam sections 56 locatedabove the sections 54 but preferably shorter than the sections 54. Theminimum length of the span is not less than the length of a single carand it may be longer, even long enough to support more than one car.There are rails 57 on this span corresponding to the track 2. At eachend of the span 53 there are shorter beams 58 that have one end flexiblyjoined at 59 to the span 53 and the other end resting on a rockerbearing 60 on the main supports 50. There are rails 61 on these sectionsthat match the track ends on the supports 50 and on the span 53.

The beams 56 of the span 53 and the confronting ends of the beams 58 areresiliently supported on the I-beam sections 54 by means of compressionsprings 62 each of which surrounds a telescoping dash-pot style of guidearrangement 63 comprising a cylinder element on the top of the sections54 and a plunger-like element on the bottom of the upper I-beam sections56, as clearly shown in FIG. 8. In addition, there are bolts 64, eachattached to a flange of a section 56 and slidably passed through aflange of beam 54, with cushioning means 65 at their lower ends. Thesebolts restrain the vertical movement of span 53 with respect to beamstructure 52.

The span 53 has one or more, preferably two, rigid holddown bracketunits 66 secured thereto, each comprising a horizontal arm 67 at thefree end of which is an upright 68. Each upright has a horizontal stud69 which carries a roller 70 at a level and in a position where the topflange 6' of the side channel 6 of a car will roll under it, the entirebracket and roller assembly comprising a hold-down bracket that willprevent the car from leaving the track either under the impact of a loador under rebound of the spring-supported span. The brackets may be onboth sides of the span 53, but if they are on one side only, as shown,they will preferably be on the side of the track opposite the loadingchute to better oppose any lateral thrust of component of force of thematerial sliding down an inclined chute into the car. It will be notedhow the construction or the car with the upwardly-flaring trough-shapedbody is arranged to provide clearance for the travel of the car underthe hold-down roller.

The Unloading Station Depending on the type of operation for which theapparatus is constructed, the unloading station may be arranged inseveral different ways, but in all cases there will be certainconstructions that will be common, and the simplest unloading stationwill be first described.

In FIG. 12 the unloading terminal is a simple incomplete circular orsemi-circular loop 75. The loop begins at ground level at 76 with anupwardly-inclined ramp which is supported on a trestle 77. At 78 thetrack begins a gradual edgewise tilt to a mid point on the loop when ithas been turned edgewise sufficient to dump the entire contents of thecars up to 90 if necessary. For example, the loop may at this point beat the edge of a landfill and as each car moves around the track it willbegin to dump its contents somewhat in advance of the position ofmaximum tilt. Beyond this point the track will start to twist back tonormal plane so that the cars will return to an upright position and thetrain will go down a ramp 76' similar to 76 onto a return track atground level. Since the cars are not disconnected, the train maycontinue to move as the cars successively dump. In fact in the processof dumping, the train twists in one direction and then in a reversedirection, the point of maximum twist progressing car-by-car toward thetrailing end of the train. track FIG. 13 shows in detail the trackarrangement at the position where the tacks is tilted to a vertical ornear vertical position. Along that edge of the track which is tilted up,there are hold-down devices 80 similar to the hold-down units 66 at theloading station. These holddown units are spaced along the track at acenter-tocenter distance less than a single car length beginning at apoint where the loaded cars are approaching a position as they movearound the track where they assume an angle of tilt of perhaps to aposition of maximum tilt and back to about the same angle, when they areno longer necessary. In this stretch of track, each car will always haveits upper channel edge 6' restrained by contact with the roller 70 of atleast one hold-down bracket.

On the low side of the track, beginning close to where the track beginsto tilt and continuing to a point where the track is almost back to anormal position are a series of car supports and retainers designatedgenerally as 90. They are preferably at a center-to-centerdistance ofless than one car length. As seen in FIG. 13, each unit 90 comprises astructure similar to the holddown units 80, each having a rigid bracketarm 91 on which is a post 92 with a roller 93 arranged to ride on thetop flange of the side channel 6 at the lower side of the car. Besidethe holddown roller 93, each unit 90 also has an elongated roller 94carried on a shaft so mounted in bearings 95 that the roller can turnfreely. The roller 94 is so positioned that the side strip -21 on thelow side of each car will ride on the roller to keep the car fromslipping sideways as it tilts progressively about its longitudinal axisfrom the normal upright position to the maximum angle of tilt and backto normal. It should be kept in mind, however, that each car is part ofa continuously-moving relatively long train, so that except for the endcars, there is a car ahead and one behind approaching or receeding fromthe position of maximum tilt. Since the cars are turned edgewise duringa substantial part of their travel around the loop and they areconnected with couplings permitting universal movement, the radius ofcurvature of the loop may be very much shorter than would be the case ifthe cars were upright. This is important in and then restored to anormal upright position as the train continues to move. The frictiondrive units are yieldably held against the driving strips withsufficient force to avoid slippage on the level and upgrade, and ondownhill grades the friction wheels at the drive stations may be drivenby the cars to provide regenerative electric braking, or mechanicalbraking, or even both.

Hold-down brackets and side roller assemblies are provided at theunloading station, as above described. By having no springs in the carswhich would compress unevenly with variations in the load, the frictiondriving means for the train and the holddown brackets and side rollersmay be set at the correct level for effective functioning.

For some cases a complete system may have but a single track with asingle train or a single track with multiple trains and sidings forpassing and preferably with a loop at each terminal. However, instead ofhaving a loop at each terminal the trains may be reversed at one or bothterminals with appropriate reversal of the driving stations.

Track-on-Track Unloading Station In line with the foregoing comments,FIGS. 14 to 17 inclusive show an arrangement where unloading may be atpreselected locations. For example, ore from a mine, coal or some othermineral may be placed in heaps along a straight reach of track. As shownin FIG. 15, the track at the unloading area has a ramp leading fromground level to an elevated straight stretch of track 101 supported on atrestle structure schematically indicated at 102. The unloadingarrangement is provided to discharge material onto any one of two ormore stations as indicated by the piles of material at 103 or anyselected position along the stretch of track 101. For this purpose thereis an unloading structure designated 104 that is movable along the track101 and which has an inclined ramp 105 at one end and another inclinedramp 106 at the other end. There are rails 107 on the structure whichslope at the ends of the respective ramps 105 and 106 onto the rails ofthe main track. These rails 107 taper at the ends where they fit againstthe rails of the main track so that the train may move onto and off fromthe movable section as smoothly as possible. The track on the movablesection starts to tilt edgewise close to the beginning of the ramp 105,reaches the maximum edgewise tilt along the central portion 108 of themovable unit and then tilts back to a normal plane where the cars areagain upright so that when they leave ramp 106 of the movable structure,they will again be in a normal upright attitude.

The construction of the movable section 104 is best seen in FIGS. 16 and17, which are somewhat schematic, In general, the structure haslongitudinallyextending inverted channels 110 that rest on the rails ofthe straight track section. They are constructed to roll, or withlubricant to slide, on the rails. These longitudinal runners 110 areconnected at frequent intervals with transversely-extending horizontalstructural sections 111 near one end of which are rigid upright sections112 wich increase in height from each sloping end toward the area ofmaximum tilt. At those areas of the track where the angle is about 90 ormore there are inclined structural sections 113 (see FIG. 16)corresponding to cross ties to which rails 107 are secured, one end ofthe sections 113 being secured to the tops of the uprights 112 and theother, lower ends being secured to the cross members 111. Where thetrack on the movable section is turned edgewise to the maximum anglewhich may be a full 90 as shown in FIG. 17, the uprights 112 are nolonger used and the cross-tie members 113 themselves are upended andwelded or otherwise rigidly secured to the cross members 111. In thislocation where the cars are turned sideways, there may be blocks ofconcrete, or other ballast 113a secured to the members 113 on the sideopposite the rails 107 to assume that the center of gravity will at alltimes be positioned to hold the sliding track section on the main track.

, On'the high end of the members 113, as shown in FIGS. 16 and 17 thereare holddown roller units 113, similar to those previously described. Atthe lower side of the tilted track the cars may be retained either asshown in FIG. 13 or FIG. 16 and for purposes of illustration we haveshown a support roller arrangement 95 as shown in FIG. 13 andcorresponding parts in FIG. 17 and 13 have corresponding referencenumerals. However, where ever it may be desirable, the support rollermay be motor driven, as is the support roller 119 in FIG. 16, and ofcourse in FIG. 16 the motor for driving the roll 119 may be omitted.

If it is necessary, one or more of the wheels or rollers 119 may bepower-driven (as shown in FIG. 16) to aid in moving the train as it ismoving over the movable unit.

The movable track unit 104 may be slid or otherwise moved along thestraight elevated track 101 so that the cars will be tilted to dumpingposition at any selected position along this track. It may be pulled orslid one way or the other by a cable and winch, for example (not shown)or by other means.

The movable loading station on a straight track as just described isprimarily designed for use in a fixed location, as for example adjacenta smelter or other operation where the bulk material which is dumpedfrom the train is processed or consumed or perhaps transferred to somelong-haul transport system such as standard railroad cars, barges, orlong-haul trucks. It has an important advantage over the arrangementshown in FIG. 12 in that the material may be dumped at any positionalong a given site to form several receiving stations such as indicatedby the piles 103 without changing the position of the main tracksthemselves. With a loop, as shown in FIG. 12, the entire unloading loopmust be moved to dump the cars in different locations. There are,however, many instances where a mobile unloader may be much more usefulor even necessary. Out invention provides such a mobile unloader for thetrain, as illustrated in FIGS. 19-23.

Referring specifically to FIGS. 19 and 20, the dumping terminal as hereshown comprises a self-propelled unit 130, with some mobile or wheeledsupport, such as the endless tracks or crawlers 131 here shown ofconventional design and the unit has a cab 130a thereon. It supports anelevated nearly circular dumping track which in its overall constructionis arranged much like the fixed track in FIG. 13. As here illustrated asone construction, the unit has heavy longitudinally extending framemembers 132 along each side. To each of these frame members at each sideof the machine is attached an upwardly-extending X-frame comprisedprincipally of intersecting structural sections 133 and 134. At the topof each of these X-frames are long downwardly and rearwardly-slopingstructural beams 135 that converge and are joined together at 136.Adjacent the forward ends of the beams are parallel forwardly anddownwardly-extending struts 137, and there is a strut 138 extendingdownwardly and outwardly from near the upper end of each beam 137, thesestruts diverging with respect to each other. A cross member 139 isconnected to the ends of the struts 138. There is a short cross member140 connecting the forward ends of the beams 137. Structural members 141extend diagonally between the ends of cross member 140 and the ends ofthe long cross-beam 139.

On the opposite end of the inclined frame structure comprising the longbeams 135 and in the area 136 there is hinged at 142 an adjustableextension 143. There is a light truss-like structure 1430 on thisextension to which is anchored a cable 144 that passes over a sheave 145on a mast 145a extending upwardly from the inclined frame structure.After passing over the sheave the cable extends down to a winch (notshown) that is controlled from the cab 130s of the mobile unit 130.Through the operation of this cable, the extension may be moved up anddown.

There is a track section 146 rigidly mounted on each side of theextension 143, the sections being simply conventionally shown but whichwould actually comprise a structural support to which rails are secured,the spacing of the rails corresponding to the spacing of the rails 2 ofthe main track. The main supporting frame has a track 147 that extendsfrom the upper end of one of the track sections 146 along the side ofone of the beams 13S and then angles away from said beam to the outerend of the beam or across frame 139 and then it extends in a semi-circlearound the fron of the frame to the other end of cross beam 139. Fromthis point it angles inwardly toward the other main beam 135 andterminates in the other pivoted track section 146 on the other side ofthe adjustable frame. Because of the extremely short radius about whichthe universallycoupled cars can turn when the cars are vertical ornearly so, the semi-circular track loop of this mobile unit is of a sizecapable of being mounted in this fashion on a mobile unit, as described.

Beginning at about the area marked 148, the track 147 begins to betilted transversely edgewise, reaching the area of maximum tilt at thefront of the frame in the semi-circle and remains at the position ofmaximum tilt past the front center of the frame and then begins togradually flatten out to become flat in the region 1480. The hold-downand side support rollers are used on the upper and lower sides'of thetilted track as described in connection with FIGS. 16 and 17 or in FIG.13 and structures for supporting the track at different angles may begenerally similar to the arrangement shown in these figures, but becauseof the small scale of the drawings and for purposes of clarity ofillustration, these details are not shown.

It will be seen that the supporting structure on the mobile unit isgenerally cantilevered, with the wider front portion balancing more orless the longer downwardly-sloping rear portion and with transversebalance be provided by a general symmetry of structure at each side ofthe longitudinal axis of the apparatus.

The free trailing ends of the rails on the pivoted extension 143 must beoperatively retained on the heads of the rails 2 of the non-movabletrack so that the train may roll from the tracks 2 onto or off fromrails of track sections 146. FIGS. 22 and 23 show one arrangementwherein the end of rail 150 forming track 146 is beveled at 151 to rideon the head of a rail 2. There is a shoe 152 on the head of the rail 2under the sloping rail 150 with a channel-like under surface so that theshoe is free to slide on the rail 2 but cannot move sideways withrespect thereof. The top of the shoe has apaced parallel vertical sideplates 153 therein between which is slidably received a vertical plate154 secured to element 155 forming part of the track structure 146. Ifdesired, guide pins 156 passing through the plate 154 and curved slots157 in the side plates 153 limit the relative arcuate movement betweenthe track sections 146 on the sides of the pivoted extension and thetrack 2.

With an arrangement such as the one described, the mobile unit maytravel on uneven ground and deviate to at least a slight extend fromabsolute in-Iine travel with the rails 2 and move back and forth alongthese rails, and of course, if the distance between the crawlers is wideenough, the unit may straddle the rails 2 and move a considerabledistance therealong. The construction described also enables the mobileunit to leave one track terminal and engage another, as herein aftermore fully described.

As indicated in FIG. 21, it is often desirable with the unloader, aswell as with the others, to have parallel tracks 157 and 158 leading toand from the machine with a conventional double cross-over arrangement159 so that the train may be selectively sent up onto the dumping loopof the track from either direction and thus selectively dump material toone side or the other of the longitudinal center of the apparatus. Withthis arrangement considerable flexibility is provided for making landfills, storage piles, leaching beds and the like before the non-movablemain tracks must be entended or shifted to another location. Also themobile unit may be at grades above or below the rails 2 since the hingedextension section 143 with its track sections 146 can be adjusted to aconsiderable variation in levels.

Loading Arrangement for Open Pit and Similar Excavations There arevarious loading arrangements that may be provided. FIG. 18 schematicallyrepresents one form of loading station for use in open pit mines, suchas those in which the walls of the pit are terraced and the diameter ofthe pit at each level progressively increased. FIG. 18 shows how a dumptruck, or a clam shell bucket or the like on one terrace may dumpmaterial into a hopper from which it is loaded onto a train on a terracebelow. In this view T designates one terrace and T a terrace above.Parallel tracks A and A2 are on a slope leading from one level toanother. One of these tracks A includes a loading station, S, such, forexample, as that shown in FIGS. 6-8. The loading station is positionedunder a hopper 165 the top of which opens at the level of the terrace T.A dump truck 166 or other material handling apparatus may dump ore orwaste into the hopper and it is discharged from the hopper into a train(not shown) on track A from a conveyor belt 167. There is a double driveunit indicated at 168. The track A extends a substantial distance beyondthe loading station and there is a switch-back 169 by which the loadedtrain may be transferred to track A2 to travel to an unloading station.There is shown over the hopper a screen or grating to separate largerpieces of rock which do not pass through the screen and which collect ona still lower terrace.

It should be understood that there may be more than one loading stationand that through the use of switches, trains may be directed toward acommon track leading to an unloading station and there may be switchesto direct different trains to different unloading stations.

Open Pit Mining or Similar Operation The diagram FIG. 24 showsschematically, but much out of proportion, an adaptation of theinvention to an open pit copper mine. The broken contour line 174 merelyindicates a pit area. The tracks and other components are out ofproportion and the numerous driving stations have not been shown.

There is a central control station 175 where movement of trains into andout of any one of several branches by the operation of track switches isdirected.

There may be a number of loading stations 176 in the pit, three beingshown, and two tracks are shown leading to each but frequently there maybe but one. Two of the stations 176 are in track loops whereas thethird, 176a at the right may be a switch-back type.

In addition to ore that is rich enough to be crushed and processed forthe recovery of metal, there will be mined lean ore that does notjustify crushing and smelting, but which is delivered to extensiveleach-beds for the acid extraction of metal, and of course there will bemuch waste that has no mineral value or only a trace and which must beremoved for disposal elsewhere.

There are generally parallel main tracks 177 leading out of the pit.Switches at 178 may direct the trains into and out of looped dumpingtrack 179 similar to the unloading station, for example, heretoforedescribed in connection with FIGS. 12 and 13. This would be for thewaste disposal. Other switches 180 in tracks 177 are for a pair ofbranch tracks 181 which in turn lead to one or more pairs of tracks181a, 181b, and 181e, for use wijh the traveling unloader 182, similarto that shown in FIGS. 19 through 23. This arrangement will provide forthe sequential loading of materials in any one of several leaching bedareas where the low-grade ore will be leached. The back-and-forth travelof the mobile unloader will permit material to be laid down insuccessive layers in the leaching beds.

The tracks 177 may extend for a considerable distance to an oreprocessing plant or smelter 183 where there may, if desired, be amovable unloader track 184 similar, for example, to the arrangementshown in FIGS. 14 to 17, inclusive.

In FIG. 24 differen types of loading and dumping or unloading stationsare shown in different locations merely to indicate the flexibility andadaptability of our invention, and all one kind of dumping station maybe used at all terminals, or various ones otherwise arranged. However,at the leaching bed area, the mobile unloader arrangement isparticularly desirable since the back-and-forth travel of the unloaderenables leaching beds to be filled in layer after layer with a minimumof labor and bull-dozing. In this operation it becomes feasible to gradea bed area, lay down a plastic covering and then develop a bed ofleaching ore by moving the mobile unloader back and forth over the bedarea, compacting the leveling the bed at least to some extent, as itdelivers the material to the bed. The leaching liquor, subsequentlyapplied to the bed, is caught by the plastic sheet and conducted to oneor more collecting outlets.

In an extensive system, such as that diagrammed in FIG. 24 the trackswitches may be remotely operated and a panel board may indicate theposition of different trains. Ordinarily the trains do not stop whenbeing loaded or unloaded but their speed may be reduced at the loadingand unloading stations. A train may be stopped and started at mostpositions by de-energizing a selected drive station and frictionallyand/or regeneratively retarding the free rotation of its driving wheelor wheels, and of course to again put the train in motion, the motor atthat station is energized to operate the friction drive. The train iscapable of making sharp turns and adapting to uneveness in the tracksand the tracks may be easily shifted and moved as operations require.Inexpensive tunnels may take the tracks in most cases under a highwayinstead of over it.

The apparatus may, of course, be used in various other fields, such forexample as the building of dams, the excavation of tunnels, the buildingof earthen dikes and the digging of ditches. It is transferable from jobto job and may be supplied to a contractor or as rental equipment. Thetracks may be shifted about, and the side dump unloading stations ofwhatever type used, may also be shifted about from time to time as maybe necessary or desirable. Where grades are very steep, and in order toavoid an excessive number of driving stations therealong, a cable andwinch arrangement may be provided for use with or in lieu of thefriction drive, and even where only the friction drive stations are usedthe grades may be steeper than those on which a locomotive could be usedbecause of the superior traction that can be exerted with fixed drivestations as herein described. Other uses and advantages will berecognized by those skilled in the art and need. not be set forth here.

We claim:

1. Industrial bulk material transportation apparatus comprising:

a. remotely separated train loading and unloading stations and a mainrailway track extending between them, the track at the unloading stationbeing progressively tilted edgewise from a normal plane through an aresufficient to tilt the cars of a train designed for use therewiththrough an angle sufficient to discharge the contents thereof and thenprogressively tilted back to a normal plane, said tilted portion of thetrack being several car lengths in extent so that different cars of atrain are tilted at different angles at the same time,

b. a train movable along the track comprising several individual wheeledcars coupled for relative rotation about their longitudinal axes wherebycars of a train moving on said tilted track may be tilted to a differentangle than the one ahead or behind, the cars being also pivotallyconnected for relative movement about an axis parallel with the axes ofthe cars across their width, each car of the train having a body and aframe on which the body is secured, the car having a drive stripextending therealong substantially the full length thereof on that sideof the car which is the lower one when the car is being tilted todischarge its contents, the frame having at least one pair of wheelsthereon arranged to roll on said track, d. spaced drive stationspositioned at intervals along the track, each station having apower-driven resilient friction element arranged to engage the drivestrips of the successive cars of a train to thereby propel the trainfrom one drive station to the next,

c. said edgewise tilted section of the track at the unloading stationhaving roller means at intervals there-along positioned to engage thedrive strips on the cars as they are moving and supporting the carsagainst side slip toward the lower side of the track while the cars aretilted, and other means at intervals along the high side of the trackarranged to engage the upper surfaces of the car frames while they areso tilted for holding the wheels of the cars against the track.

2. Apparatus as defined in claim 1 wherein at least some of the rollermeans that engage the drive strips when the cars are tilted arepower-driven for moving the train and wherein there are also rollers atintervals along the lower side of the track at the unloading stationwhich are arranged to engage the upper surface of the tilted car framesalong the lower sides thereof and confine the wheels on the lower sidesagainst the tracks.

3. Apparatus as defined in claim 1 in which the car frames havegenerally trough-like bodies thereon which have outwardly-flaring sides,each frame having a structural section along each side which issubstantially the full length of the car, and hold-down rollers spacedalong the higher side of the tilted track at the unloading station sopositioned that they are received in the space above the frames of thecars and the flaring sides of the bodies and roll on said structuralsection to confine the wheels of the cars against the rails, saidstructural sections also having the said drive strip secured thereto.

4. Apparatus as defined in claim 3 wherein the cars are each constructedwith an axle and wheels attached directly to the frame without springswhereby the said structural sections and drive strips of the severalcars are at the same level when the train is on a level trackirrespective of variations in the loads in the cars.

5. Apparatus as defined in claim 3 in which the drive strips are on theexterior side faces of said structural frame members at each side ofeach car.

6. Apparatus as defined in claim 5 in which the drive stations each havea power-driven wheel that is resiliently urged against the said drivestrips, there being at each drive station other means engaging the drivestrip on the opposite sides of the cars to oppose the lateral thrust ofthe driven wheel against the cars.

7. Apparatus as defined in claim 1 in which the several cars of thetrain have a horizontal strip therealong extending laterally thereof onat least one side, the driving station having upper and lower frictionwheels arranged to resiliently engage the upper and lower surfaces ofsaid strip with the upper friction wheel opposing any upward thrustexerted by the lower friction wheel against said strip, and means fordriving said friction wheels.

8. Apparatus as defined in claim I in which the main track at theunloading station has a movable secondary track section thereon with themain track extending continuously under the movable secondary tracksection, said movable section being arranged to effect the tilting ofthe cars and the restoring of them to normal position, said movablesection being so arranged that the train will move up onto it from themain track and then return to the main track after the cars have beendumped.

9. Apparatus as defined in claim 1 in which the unloading stationcomprises a mobile unit that may travel back and forth along the maintrack, the track extending continuously under the mobile unit, themobile unit having a ramp engaged with the rails of the main track toand from which the train may move from the main track onto the ramp andfrom the ramp back to the main track, the mobile unit itself having thetrack thereon progressively tilted edgewise from a starting position ofmaximum tilt and back to normal for dumping the cars after the trainmoves up the ramp and before it moves down the ramp to return to themain track.

10. Apparatus as defined in claim 1 in which the main track has twobranches side-by-side and the unloading station comprises aself-propelled unitary vehicle that has endless tractor treads to moveover the earth unsupported by the main track, said vehicle having astructural framework supported thereon and extending upwardly above it,the structural framework comprising an inclined ramp that slopesdownwardly and rearwardly with two parallel tracks thereon and a loopedtrack support, the looped track support having a generally semi-circularlooped track thereon connecting the upper ends of the two tracks on theramp, said looped track being gradually tilted outwardly edgewise from anormal plane to a substantially vertical plane and then tilted in thereverse direction to a normal position at the other end of the loop,said looped track having means at intervals thereabout arranged toprovide a rolling support bearing against said drive strips on the lowersides of the tilted cars and other means along the looped track on boththe high and low sides for holding the car wheels on the looped trackwhen the cars are tilted to an angle to discharge a load therefrom, saidramp terminating with one of its two parallel tracks extending up fromone branch of the main track and the other extending up from the otherbranch of the main track so arranged that a train may move from onetrack up the ramp, around the loop and down the ramp to the other maintrack.

11. The invention defined in claim wherein the dual branches of the maintrack adjacent the unloading terminal are provided with double switchesso arranged that the direction of travel of a train up the ramp andaround the loop may be selectively reversed to change the position wherethe dumping area of the cars begins to take place.

12. Apparatus for dumping a train of open top cars connected foruniversal relative movement that are propelled along a main trackcomprising:

a. a movable elevated track section having an inclined ramp portion witha two-rail track thereon that extends from the elevated track to thetwo-rail main track, the rails on said ramp slidably engaging the railsof said main track whereby the movable track section may be moved alongthe main track and the train may travel up or down the ramp,

b. the said movable elevated track being twisted edgewise to asubstantially vertical position during a portion of its length wherebycars of the train moving along the tilted elevated track are tiltedsideways through an arc sufficient to discharge the contents of the carsto one side of the elevated track,

0. hold-down means at spaced intervals along the elevated tilted tracksection at the high side of the tilted track each comprising a rollerarranged to bear against a member extending along the upper longitudinaledges of the cars to hold the cars against the track, and roller meansat intervals along the lower side of said section positioned to engage amember extending along each of the cars at their low sides to restrainthe cars from side slip while they are being tilted and dumped.

13. Apparatus as defined in claim 12 wherein said elevated tilted tracksection is supported on and carried by a vehicle.

14. Apparatus as defined in claim 12 wherein said elevated track sectionis mounted on and slidable along a straight reach of the normal two-railmain track.

15. Apparatus as defined in claim 1 wherein the cars are springless andthe loading station comprises a resiliently-supported track span of atleast one car length interposed between two fixed track ends withconnections between said span and the track ends which permit verticalmovement of the span while effectively maintaining the continuity of thetrack from one track end to the other.

16. Apparatus as defined in claim 15 wherein there is a loading deviceover said resiliently-supported track span arranged to drop bulkmaterial into cars moving along said span.

17. Apparatus as defined in claim 1 wherein each drive station comprisesan upright frame structure at one side of the track, alaterally-extending frame pivotally hung in the upright frame forrotation in a vertical arc, a cradle hung from the laterally-extendingframe in which is set a combined motor, brake and speedreducing gear,the speed-reducing gear having a vertical driven shaft with a frictionwheel thereon, said motor and reducing gear being so positioned in thecradle with reference to the axis about which the laterallyextendingframe pivots that the wheel is yieldably biased by the combined weightthereof to bear against the drive strip of a car positioned on the trackalongside the wheel, and spring means for increasing the biasingpressure of the wheel against a car which is so positioned.

18. Apparatus as defined in claim 1 wherein the body and frame of eachcar are substantially coextensive and the body is of a trough-likesection open at the top, only the front and rear cars having transverseend walls for the body, the bodies of the intermediate cars beingopen-ended, each car except one end car having a flexible trough-likeapron fixed thereto at one end only that extends into the trough-shapedopen end of the adjacent car for support but to which it is unattachedwhereby the cars provide a substantially continuous trough-likematerial-receiving space from one end of the train to the other.

19. Bulk material transporting apparatus for use in open pit miningcomprising:

a. a railway track extending from within the pit to separated unloadingstations, one of which is at an ore processing plant, another at a dump,and another at a leaching bed area, the track having switches forselectively directing a train into or out of any one of said areas,

b. the track in the mine having branches leading to different loadingstations in the mine with switches for selectively directing a train toor from any one of said loading stations,

c. a train movable over said track comprising a connected series ofcars, each car having a frame and a body, each car having a drive stripalong each side edge thereof, each car having a trough-like body on theframe open-at the top,

d. train driving stations at intervals along the track having driveunits comprising power-driven friction wheels that resiliently bearagainst and engage the drive strips on the cars for propelling thetrain, said units being also arranged with brakes for retardingdown-grade travel of the trains or stopping them,

. each unloading station comprising an elevated the unloading station atthe leaching bed area having the said elevated track section on a mobilesupport that may travel on the earth at the end of the track that leadsto said leaching bed area whereby said mobile unit may travel back andforth relative to said track end to progressively build up a leachingbed, the track on the mobile unit being engaged with said track endthrough an inclined ramp the lower end of which is adjustable verticallyto accommodate the change in height of the leaching bed as it is builtup, the ramp having track means thereon extending between said track endand said elevated track section.

20. The apparatus of claim 19 wherein there is a central control area inthe pit for routing empty trains to selected loading areas and loadedtrains to a selected unloading station, said trains being controlledentirely from said control station with no crew being required on anytrain.

1. Industrial bulk material transportation apparatus comprising: a.remotely separated train loading and unloading stations and a mainrailway track extending betwEen them, the track at the unloading stationbeing progressively tilted edgewise from a normal plane through an arcsufficient to tilt the cars of a train designed for use therewiththrough an angle sufficient to discharge the contents thereof and thenprogressively tilted back to a normal plane, said tilted portion of thetrack being several car lengths in extent so that different cars of atrain are tilted at different angles at the same time, b. a trainmovable along the track comprising several individual wheeled carscoupled for relative rotation about their longitudinal axes whereby carsof a train moving on said tilted track may be tilted to a differentangle than the one ahead or behind, the cars being also pivotallyconnected for relative movement about an axis parallel with the axes ofthe cars across their width, c. each car of the train having a body anda frame on which the body is secured, the car having a drive stripextending therealong substantially the full length thereof on that sideof the car which is the lower one when the car is being tilted todischarge its contents, the frame having at least one pair of wheelsthereon arranged to roll on said track, d. spaced drive stationspositioned at intervals along the track, each station having apower-driven resilient friction element arranged to engage the drivestrips of the successive cars of a train to thereby propel the trainfrom one drive station to the next, e. said edgewise tilted section ofthe track at the unloading station having roller means at intervalsthere-along positioned to engage the drive strips on the cars as theyare moving and supporting the cars against side slip toward the lowerside of the track while the cars are tilted, and other means atintervals along the high side of the track arranged to engage the uppersurfaces of the car frames while they are so tilted for holding thewheels of the cars against the track.
 2. Apparatus as defined in claim 1wherein at least some of the roller means that engage the drive stripswhen the cars are tilted are power-driven for moving the train andwherein there are also rollers at intervals along the lower side of thetrack at the unloading station which are arranged to engage the uppersurface of the tilted car frames along the lower sides thereof andconfine the wheels on the lower sides against the tracks.
 3. Apparatusas defined in claim 1 in which the car frames have generally trough-likebodies thereon which have outwardly-flaring sides, each frame having astructural section along each side which is substantially the fulllength of the car, and hold-down rollers spaced along the higher side ofthe tilted track at the unloading station so positioned that they arereceived in the space above the frames of the cars and the flaring sidesof the bodies and roll on said structural section to confine the wheelsof the cars against the rails, said structural sections also having thesaid drive strip secured thereto.
 4. Apparatus as defined in claim 3wherein the cars are each constructed with an axle and wheels attacheddirectly to the frame without springs whereby the said structuralsections and drive strips of the several cars are at the same level whenthe train is on a level track irrespective of variations in the loads inthe cars.
 5. Apparatus as defined in claim 3 in which the drive stripsare on the exterior side faces of said structural frame members at eachside of each car.
 6. Apparatus as defined in claim 5 in which the drivestations each have a power-driven wheel that is resiliently urgedagainst the said drive strips, there being at each drive station othermeans engaging the drive strip on the opposite sides of the cars tooppose the lateral thrust of the driven wheel against the cars. 7.Apparatus as defined in claim 1 in which the several cars of the trainhave a horizontal strip therealong extending laterally thereof on atleast one side, the driving station having upper and lower frictionWheels arranged to resiliently engage the upper and lower surfaces ofsaid strip with the upper friction wheel opposing any upward thrustexerted by the lower friction wheel against said strip, and means fordriving said friction wheels.
 8. Apparatus as defined in claim 1 inwhich the main track at the unloading station has a movable secondarytrack section thereon with the main track extending continuously underthe movable secondary track section, said movable section being arrangedto effect the tilting of the cars and the restoring of them to normalposition, said movable section being so arranged that the train willmove up onto it from the main track and then return to the main trackafter the cars have been dumped.
 9. Apparatus as defined in claim 1 inwhich the unloading station comprises a mobile unit that may travel backand forth along the main track, the track extending continuously underthe mobile unit, the mobile unit having a ramp engaged with the rails ofthe main track to and from which the train may move from the main trackonto the ramp and from the ramp back to the main track, the mobile unititself having the track thereon progressively tilted edgewise from astarting position of maximum tilt and back to normal for dumping thecars after the train moves up the ramp and before it moves down the rampto return to the main track.
 10. Apparatus as defined in claim 1 inwhich the main track has two branches side-by-side and the unloadingstation comprises a self-propelled unitary vehicle that has endlesstractor treads to move over the earth unsupported by the main track,said vehicle having a structural framework supported thereon andextending upwardly above it, the structural framework comprising aninclined ramp that slopes downwardly and rearwardly with two paralleltracks thereon and a looped track support, the looped track supporthaving a generally semi-circular looped track thereon connecting theupper ends of the two tracks on the ramp, said looped track beinggradually tilted outwardly edgewise from a normal plane to asubstantially vertical plane and then tilted in the reverse direction toa normal position at the other end of the loop, said looped track havingmeans at intervals thereabout arranged to provide a rolling supportbearing against said drive strips on the lower sides of the tilted carsand other means along the looped track on both the high and low sidesfor holding the car wheels on the looped track when the cars are tiltedto an angle to discharge a load therefrom, said ramp terminating withone of its two parallel tracks extending up from one branch of the maintrack and the other extending up from the other branch of the main trackso arranged that a train may move from one track up the ramp, around theloop and down the ramp to the other main track.
 11. The inventiondefined in claim 10 wherein the dual branches of the main track adjacentthe unloading terminal are provided with double switches so arrangedthat the direction of travel of a train up the ramp and around the loopmay be selectively reversed to change the position where the dumpingarea of the cars begins to take place.
 12. Apparatus for dumping a trainof open top cars connected for universal relative movement that arepropelled along a main track comprising: a. a movable elevated tracksection having an inclined ramp portion with a two-rail track thereonthat extends from the elevated track to the two-rail main track, therails on said ramp slidably engaging the rails of said main trackwhereby the movable track section may be moved along the main track andthe train may travel up or down the ramp, b. the said movable elevatedtrack being twisted edgewise to a substantially vertical position duringa portion of its length whereby cars of the train moving along thetilted elevated track are tilted sideways through an arc sufficient todischarge the contents of the cars to one side of the elevated track, c.hold-down means at spaced intErvals along the elevated tilted tracksection at the high side of the tilted track each comprising a rollerarranged to bear against a member extending along the upper longitudinaledges of the cars to hold the cars against the track, and roller meansat intervals along the lower side of said section positioned to engage amember extending along each of the cars at their low sides to restrainthe cars from side slip while they are being tilted and dumped. 13.Apparatus as defined in claim 12 wherein said elevated tilted tracksection is supported on and carried by a vehicle.
 14. Apparatus asdefined in claim 12 wherein said elevated track section is mounted onand slidable along a straight reach of the normal two-rail main track.15. Apparatus as defined in claim 1 wherein the cars are springless andthe loading station comprises a resiliently-supported track span of atleast one car length interposed between two fixed track ends withconnections between said span and the track ends which permit verticalmovement of the span while effectively maintaining the continuity of thetrack from one track end to the other.
 16. Apparatus as defined in claim15 wherein there is a loading device over said resiliently-supportedtrack span arranged to drop bulk material into cars moving along saidspan.
 17. Apparatus as defined in claim 1 wherein each drive stationcomprises an upright frame structure at one side of the track, alaterally-extending frame pivotally hung in the upright frame forrotation in a vertical arc, a cradle hung from the laterally-extendingframe in which is set a combined motor, brake and speed-reducing gear,the speed-reducing gear having a vertical driven shaft with a frictionwheel thereon, said motor and reducing gear being so positioned in thecradle with reference to the axis about which the laterally-extendingframe pivots that the wheel is yieldably biased by the combined weightthereof to bear against the drive strip of a car positioned on the trackalongside the wheel, and spring means for increasing the biasingpressure of the wheel against a car which is so positioned. 18.Apparatus as defined in claim 1 wherein the body and frame of each carare substantially coextensive and the body is of a trough-like sectionopen at the top, only the front and rear cars having transverse endwalls for the body, the bodies of the intermediate cars beingopen-ended, each car except one end car having a flexible trough-likeapron fixed thereto at one end only that extends into the trough-shapedopen end of the adjacent car for support but to which it is unattachedwhereby the cars provide a substantially continuous trough-likematerial-receiving space from one end of the train to the other. 19.Bulk material transporting apparatus for use in open pit miningcomprising: a. a railway track extending from within the pit toseparated unloading stations, one of which is at an ore processingplant, another at a dump, and another at a leaching bed area, the trackhaving switches for selectively directing a train into or out of any oneof said areas, b. the track in the mine having branches leading todifferent loading stations in the mine with switches for selectivelydirecting a train to or from any one of said loading stations, c. atrain movable over said track comprising a connected series of cars,each car having a frame and a body, each car having a drive strip alongeach side edge thereof, each car having a trough-like body on the frameopen at the top, d. train driving stations at intervals along the trackhaving drive units comprising power-driven friction wheels thatresiliently bear against and engage the drive strips on the cars forpropelling the train, said units being also arranged with brakes forretarding down-grade travel of the trains or stopping them, e. eachunloading station comprising an elevated track section having a portionof its length arranged to progressively twist a train moving therealongsideways To successively turn the cars from a normal upright positionsideways through an arc sufficient to discharge from each car in turnall of its load and then return the cars to an upright position, f. theunloading station at the leaching bed area having the said elevatedtrack section on a mobile support that may travel on the earth at theend of the track that leads to said leaching bed area whereby saidmobile unit may travel back and forth relative to said track end toprogressively build up a leaching bed, the track on the mobile unitbeing engaged with said track end through an inclined ramp the lower endof which is adjustable vertically to accommodate the change in height ofthe leaching bed as it is built up, the ramp having track means thereonextending between said track end and said elevated track section. 20.The apparatus of claim 19 wherein there is a central control area in thepit for routing empty trains to selected loading areas and loaded trainsto a selected unloading station, said trains being controlled entirelyfrom said control station with no crew being required on any train.